https://commons.ru.ac.za/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://commons.ru.ac.za/vital/access/manager/Repository/vital:931 Wed 12 May 2021 23:08:04 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1407 Wed 12 May 2021 22:43:54 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4286 Wed 12 May 2021 22:28:40 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3665 Wed 12 May 2021 20:37:09 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4557 Wed 12 May 2021 20:17:39 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5586 Wed 12 May 2021 20:11:35 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5609 Wed 12 May 2021 19:43:43 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2447 Wed 12 May 2021 19:37:40 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5610 Wed 12 May 2021 18:41:58 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1840 Wed 12 May 2021 18:39:28 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4741 Wed 12 May 2021 18:16:27 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5621 Wed 12 May 2021 18:05:21 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3888 Wed 12 May 2021 17:29:53 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4562 Co(II) > Ni(II). The Schiff-base derivatives were prepared from the ligands and para-methoxysalicylaldehyde and their Cu(II) complexes were synthesized in order to determine their biological activity. The Schiff-base ligands were found to be less active than their parent ligands. The Cu(II) complexes are not soluble in water, DMSO or DMF, as a result and could not be evaluated for their biological activity. Based on the good results from the antimicrobial evaluation, the antiplasmodial activity of some of the Co(II), Ni(II) and Cu(II) complexes of the thiomethylated ligands against Plasmodium falciparum (FCR-3) was determined. At 50 μM concentration level, the Cu(II) complexes show activity equal or better than the prophylactic chloroquine. The Cu(II) complexes with the methoxy-substituted demonstrated exceptional activity but their Co(II) and Ni(II) analogues did not show any activity. The cytotoxicity of the active Cu(II) complexes at 50 μM concentration was determined against the breast cancer cell line (MDA-MB-231). The compounds destroyed the cancer cell in the range of 28–40%, thus showing their preferred activity against the parasitic cell instead of the cancer cell. The selectivity demonstrated by these compounds have shown them to be potential antimalarial agents and this could be further investigated.]]> Wed 12 May 2021 17:24:20 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3337 Wed 12 May 2021 17:08:03 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4281 Ni²⁺ > Zn²⁺ > Cd²⁺> Co²⁺ was achieved as a function of pH. At pH 1.65 the extracted copper, from a synthetic mixture of the base metals reached 90.13(±0.90)%, and through a two-step extraction process 98.22(±0.29)% copper was recovered with negligible nickel and cobalt impurities. Stripping of the copper from the loaded organic phase using TraceSelect sulphuric acid at pH 0.35 yielded 96.60(±0.44)% of the loaded quantity after the second stage of stripping. The separation of Ni²⁺ from the borderline and hard acids; Co²⁺, Cu²⁺, Zn²⁺, Fe2²⁺, Fe²⁺, Mn²⁺, Mg2²⁺ and Ca²⁺ at a pH range of 0.5-3.5 with OPIM and DNNSA was acvieved to the tune of a ΔpH½≈ 1.6 with respect to cobalt from a sulfate and sulfate/chloride media. A three-stage counter-current extraction of Ni²⁺, at the optimized pH of 1.89, from a synthetic mixture of Ni²⁺, Co²⁺ and Cu²⁺, yielded 99.01(±1.79)%. The total co-extracted Cu²⁺ was 48.72(±0.24)% of the original quantity in the mixture, and it was 19.85(±0.28%) for Co²⁺. The co-extracted Cu²⁺ was scrubbed off from the loaded organic phase at pH≈8.5 by using an ammonium buffer, while co-extracted Co²⁺ was selectively and quantitatively stripped with H₂SO₄ at pH 1.64. The total recovery of Ni²⁺ by stripping at pH 0.32 was 94.05(±1.70)%. In the solid-liquid system, Ni²⁺ was separated from Co²⁺, Cu²⁺, and Fe²⁺ with the microspherical resins funtionalised with 2,2′-pyridylimidazole by a separation factor (β) in the range 22-45. Electrospun nanofibers as sorbents yielded high sorption capacity in the range of 0.97 - 1.45 mmol.g⁻¹ for the same metals ions. Thus, 1-octylimidazole-2-aldoxime (OIMOX), and1-octyl-2-(2′-pyridyl)imidazole (OPIM) can be effectively utilized alongside DNNSA as a co-extractant in the separation of Cu²⁺ and Ni²⁺ respectively from base metals in acidic sulfate medium in a solvent extraction process, and the latter as a selective ligand in the solid-liquid separation of Ni²⁺ from Co²⁺, Cu²⁺, and Fe²⁺.]]> Wed 12 May 2021 16:26:16 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5397 Wed 12 May 2021 16:16:19 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1888 Wed 12 May 2021 16:03:14 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:6023 Wed 12 May 2021 15:59:29 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:6052 Wed 12 May 2021 15:55:13 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4439 Wed 12 May 2021 15:44:41 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1891 Wed 12 May 2021 15:44:06 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3411 Thu 13 May 2021 13:55:25 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2166 Thu 13 May 2021 10:12:11 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3616 Thu 13 May 2021 09:56:44 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4278 Thu 13 May 2021 07:14:17 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5198 Thu 13 May 2021 06:45:57 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4728 Thu 13 May 2021 06:21:29 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2517 Thu 13 May 2021 06:20:31 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4729 Thu 13 May 2021 05:45:42 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5587 Thu 13 May 2021 05:39:45 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2752 Thu 13 May 2021 05:33:47 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4555 Thu 13 May 2021 05:23:51 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5504 Thu 13 May 2021 05:20:46 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4060 Thu 13 May 2021 05:15:09 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1314 Thu 13 May 2021 04:59:12 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3555 Thu 13 May 2021 04:42:13 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5585 Thu 13 May 2021 04:38:58 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4733 Thu 13 May 2021 04:22:25 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4915 2 wt %) crystallise Fe-Ti oxides early whereas low H2O magmas (< 1 wt %) crystallise oxides late. Early pulses of H2O-poor magma crystallise a sequence of plag+cpx+Fe-Ti oxide (±ol). Later pulses of H2Orich magma subsequently intrude the partially crystallised cumulate sequence incorporating and consuming previously crystallised silicates with subsequent early crystallisation of Ti-magnetite and formation of ore layers. H2O-rich magmas likely have suspended Ti-magnetite microphenocrysts as well, which crystallise at depth in the plumbing system. This model can account for the various characteristic features of the Fe-Ti oxide ore layers at the Panzhihua intrusion as well as other Fe-Ti oxide ore bearing intrusions in the region.]]> Thu 13 May 2021 03:57:26 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4277 Thu 13 May 2021 03:57:19 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5588 Thu 13 May 2021 03:05:37 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1400 Thu 13 May 2021 02:49:32 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1887 Thu 13 May 2021 02:38:21 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1033 Thu 13 May 2021 01:50:13 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3508 Thu 13 May 2021 01:44:54 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5182 Thu 13 May 2021 01:18:01 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5396 Thu 13 May 2021 01:11:32 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:5386 Thu 13 May 2021 01:05:30 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:3887 Thu 13 May 2021 00:48:55 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:6024 Thu 13 May 2021 00:27:55 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:4282 Thu 13 May 2021 00:27:23 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2736 Thu 13 May 2021 00:12:18 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:1836 Thu 06 Jul 2023 12:06:44 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2894 Mon 15 Aug 2022 13:28:48 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2531 Mon 10 Oct 2022 14:29:46 SAST ]]> https://commons.ru.ac.za/vital/access/manager/Repository/vital:2530 Mon 10 Oct 2022 14:29:19 SAST ]]>